/**
 * @author alteredq / http://alteredqualia.com/
 * @author mr.doob / http://mrdoob.com/
 */

export const Detector = {
  canvas: !!window.CanvasRenderingContext2D,
  webgl: (function() {
    try {
      return (
        !!window.WebGLRenderingContext &&
        !!document.createElement("canvas").getContext("experimental-webgl")
      );
    } catch (e) {
      return false;
    }
  })(),
  workers: !!window.Worker,
  fileapi: window.File && window.FileReader && window.FileList && window.Blob,

  getWebGLErrorMessage: function() {
    var element = document.createElement("div");
    element.id = "webgl-error-message";
    element.style.fontFamily = "monospace";
    element.style.fontSize = "13px";
    element.style.fontWeight = "normal";
    element.style.textAlign = "center";
    element.style.background = "#fff";
    element.style.color = "#000";
    element.style.padding = "1.5em";
    element.style.width = "400px";
    element.style.margin = "5em auto 0";

    if (!this.webgl) {
      element.innerHTML = window.WebGLRenderingContext
        ? [
            'Your graphics card does not seem to support <a href="http://khronos.org/webgl/wiki/Getting_a_WebGL_Implementation" style="color:#000">WebGL</a>.<br />',
            'Find out how to get it <a href="http://get.webgl.org/" style="color:#000">here</a>.'
          ].join("\n")
        : [
            'Your browser does not seem to support <a href="http://khronos.org/webgl/wiki/Getting_a_WebGL_Implementation" style="color:#000">WebGL</a>.<br/>',
            'Find out how to get it <a href="http://get.webgl.org/" style="color:#000">here</a>.'
          ].join("\n");
    }

    return element;
  },

  addGetWebGLMessage: function(parameters) {
    var parent, id, element;

    parameters = parameters || {};

    parent =
      parameters.parent !== undefined ? parameters.parent : document.body;
    id = parameters.id !== undefined ? parameters.id : "oldie";

    element = Detector.getWebGLErrorMessage();
    element.id = id;

    parent.appendChild(element);
  }
};
